How Much Gas Does Filling a Bath Cost
Heating 200 L of bath water from 15 to 40 C with city gas (45 MJ/m3, 85% efficiency, 200 JPY/m3) costs about 109 JPY. Heat needed = 4.186 x 200 x 25 = 20930 kJ.
Open the interactive Everyday Lifestyle tool →Key facts
| Heat needed | 4.186 x L x deltaT (kJ) |
|---|---|
| deltaT | 25 K (15 to 40 C) |
| Heater efficiency | 85% |
| 200 L bath (city gas) | ~109 JPY |
| 200 L bath (LP gas) | ~295 JPY |
Frequently asked questions
How much does one bath cost in gas?
About 109 JPY for 200 L heated 15 to 40 C with city gas at 200 JPY/m3 and 85% efficiency.
Why is LP gas more expensive?
At about 600 JPY/kg, the same 200 L bath costs around 295 JPY with LP gas.
How is the heat requirement found?
Heat (kJ) = 4.186 x liters x temperature rise. For 200 L and 25 K it is 20930 kJ.
Related pages
Bath Hot Water Gas Cost is part of Everyday Lifestyle on GOAT Lab — a free reference you can use without signing up, and it works offline. Open the tool above for any custom value.
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